1840 - 1899
May – The first known instance of church discipline related to same-sex sexual activity was an excommunication for the alleged bisexual behavior of 37-year-old church leader John Bennett:266–267 who was accused of "buggery" by Joseph Smith's brother William in The Waspnewspaper. Historian Samuel Taylor also alleged that Joseph Smith caught Bennett having sex with 21-year-old Francis Higbee:168 though these interpretations of the accounts and the homosexual allegations against Bennett have been challenged.:165–171
- 1851 – The church-controlled legislature of the newly formed Utah territory passed the first law addressing same-sex sexual behavior banning any "man or boy" from "sexual intercourse with any of the male creation" with penalties left to the courts' discretion.:1200 Brigham Young acted as both Utah governor and church president in the theocratic government and oversaw the selection of the legislators.
- April – The apostle Parley Pratt taught that God destroyed Sodom due to its "lawless abominations" and for predisposing its children "to be fully given to strange and unnatural lusts, appetites, and passions".:296, 412 This contrasted with church founder Joseph Smith's teaching a decade earlier that it had been destroyed for rejecting the prophets (rather than citing the traditional sexual interpretation).:296, 409 
- April – The church's newspaper printed an article in which mission president Nathanial Vary Jones of the East India Mission in Calcutta, India falsely states that around the year 1700 the people of Burma (Myanmar) were about to become extinct because the men were practicing "the crime of Sodomy" instead of procreating with the women until the king and queen decreed that the women should wear clothing that exposed more skin in hopes of "reclaiming their men" which prevented their people's extinction.
- April – Travelling bishop and later church historian Milton Musser wrote that Salt Lake City member Almerin Grow had demonstrated odd behavior and was wearing his wife's clothing in one of the first reported instances of gender non-conforming dress in the Mormon community. Church president Young subsequently sent him south to "never return," so Grow appointed Musser as guardian of his daughter.
- April – Church president Brigham Young stated that "men will be sealed to men back to Adam" in reference to same-sex sealings in which men were sealed to other unrelated men in the Law of Adoption practiced in early Mormonism.:414
- February – Seventeen-year-old, George Naylor was sent on a mission to Arizona to separate him from his 28-year-old non-Mormon lover Frank Wells by church leaders citing their "scandal and improper connexion [sic]".:1200 There were no recorded excommunications for homosexual conduct under Brigham Young's time as church president (i.e. 1845–1877).:274
- November – Twenty-six-year-old Arthur Bruce Taylor (1853–1924?), the son of then current church president John Taylor, had a long discussion with second counselor Joseph F. Smith who wrote in his journal that Bruce was "acane!". Smith had served a church mission in Hawaii where he became acquaintance with the Aikane custom where young males were socially acceptable sexual companions of older male leaders. Soon after this meeting Bruce left the Mormon church and moved to Oregon where he never married.:40–41,232
- 1885 – Brigham Morris Young, a founder of the church Young Men's program and a son of church president Young, began performing in drag as a Vaudeville female impersonator Madam Pattirini. He sang opera in falsetto throughout Utah into the early 1900s, and his gender-non-conforming act was well-received at church social events.:232 While historical evidence does not point to Young being a sexual or gender minority, it has been speculated by historian Michael Quinn that Mormon Tabernacle Choir director Evan Stephens (who also performed in drag during the late 1800s) was physically attracted to other males.:235–237
1886 – The Salt Lake City Bohemian Club is founded,:69–70 becoming a safe haven for homosexual persons, including many current and former Mormons, by 1905.:69,71 By 1908 the club's discussions and association's became more overtly homosexual:73 with lesbian club member Mildred Berryman (who was Mormon for a time):69,226–228 beginning her thesis The Psychological Phenomena of the Homosexual:223 in 1928:228 on 23 lesbian women and 9 gay men, many of whom she met through the club.:20 :69, 73 Berryman reported being acquainted with one hundred homosexual persons in Salt Lake.:222 The Bohemian Club continued until 1942.:73
- 1892? – In the early 1890s, sometime around the age of 20, famed actress Maude Adams would enter her first long-term, same-sex relationship, staying together with Lillie Florence until Florence passed away in 1901. She was born in Salt Lake City to a Mormon mother and spent some of her early years from age 9 to 13 being raised in Salt Lake City by her Mormon grandmother and cousins.:135–136 Although it is unknown whether Adams had ever identified as Mormon like her mother, she was never baptized Presbyterian despite attending one of their school and never joined Catholicism despite some stays at nunneries. She had additionally referred to her non-Mormon father as a "gentile", and invited the Mormon Tabernacle Choir to her 39th birthday performance.:139
- January – The apostle Brigham Young Jr. resigns his position over the Brigham Young Trust Co. in protest of the board's decision to rent church-owned buildings on Commercial Street (now called Regent St.) to brothels. Some raids of prostitution houses there arrested male prostitutes for other men.:424 The red-light district of Salt Lake centered around Regent Street and Plumb Alley.:19 Church property continued to be rented to brothels (which sometimes had male prostitutes) for fifty years until 1941.:433
- February – Four male prostitutes are arrested in Eureka, Utah at the state's only all-male brothel. Those arrested included a 15-year-old Mormon.:424
- October – During the October General Conference, First Presidency member George Cannon used the media attention on the 1895 conviction and two-year imprisonment of famed Irish poet Oscar Wilde as an opportunity to condemn homosexual behavior as an "abominable", "filthy", "nameless crime" that "caused the utter destruction of Sodom and Gomorrah". He continued stating that the only way to stop these "dreadful practices" was "by the destruction of those who practice them" and "for the Lord to wipe them out" noting that "if a little nest of them were left ... they would soon corrupt others".